nir: Separate texture from sampler in nir_tex_instr

This commit adds the capability to NIR to support separate textures and
samplers.  As it currently stands, glsl_to_nir only sets the texture deref
and leaves the sampler deref alone as it did before and nir_lower_samplers
assumes this.  Backends can still assume that they are combined and only
look at only at the texture index.  Or, if they wish, they can assume that
they are separate because nir_lower_samplers, tgsi_to_nir, and prog_to_nir
all set both texture and sampler index whenever a sampler is required (the
two indices are the same in this case).

Reviewed-by: Kenneth Graunke <[email protected]>

1 files changed, 8 insertions, 3 deletions

diff --git a/src/compiler/nir/nir_opt_constant_folding.c b/src/compiler/nir/nir_opt_constant_folding.c
index 20b31a8110c..04876a42fd7 100644
--- a/src/compiler/nir/nir_opt_constant_folding.c
+++ b/src/compiler/nir/nir_opt_constant_folding.c
@@ -136,10 +136,15 @@ constant_fold_intrinsic_instr(nir_intrinsic_instr *instr)
 static bool
 constant_fold_tex_instr(nir_tex_instr *instr)
 {
+   bool progress = false;
+
    if (instr->texture)
-      return constant_fold_deref(&instr->instr, instr->texture);
-   else
-      return false;
+      progress |= constant_fold_deref(&instr->instr, instr->texture);
+
+   if (instr->sampler)
+      progress |= constant_fold_deref(&instr->instr, instr->sampler);
+
+   return progress;
 }
 
 static bool